1. Field of the Invention
The present invention relates to a reinforcing material for concrete. The reinforcing material is of the type which incorporates a multitude of relatively short and substantially straight steel reinforcing elements with substantially rectangular cross section and small thickness in relation to their length and width. These reinforcing elements are intended to be uniformly distributed and in principle randomly orientated in the concrete.
In the present context "concrete" means primarily cement concrete, i.e. a hardened mixture of cement, sand and water, with or without additives such as stone materials, but also other types of concrete such as asphalt concrete. But in certain cases the term "concrete " is also used to define in a general way the unhardened mixture. Further, "steel" means a material with the element iron as its principle component, produced by a smelting process or other suitable method, e.g. by direct reduction, and with a carbon content of between 0% and about 2.0%, preferably not exceeding about 0.3%. It must always, however, be ensured that the reinforcing elements are not brittle and easily crushed, but possess a certain flexibility and ductility so that they stand being mixed with unhardened concrete without being crushed. As a rule, the hardness of the flakes should be at most about HRC (an equal sign) 50. Temperable steels may require dead-soft annealing to give the reinforcing elements the desired properties.